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1998 TOYOTA TACOMA
2.7L I4•RWD•AUTOMATIC•gas
5 active safety recalls on this vehicle — view recalls
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Repairs0Labor1040Torque1598Fluid17DTC3336Battery2Maintenance0Recalls5
P0941moderate severityPowertrain

Hydraulic Oil Temperature Sensor Circuit Intermittent/Erratic

on 1998 Toyota Tacoma 2.7L I4 · RWD

What this code means

The hydraulic oil temperature sensor signal is intermittent or erratic. Loose connections or a failing sensor are common culprits.

Symptoms

  • Intermittent transmission warning light
  • Unpredictable shift behavior
  • Fluctuating temperature readings

Common causes

  • Loose or corroded connector
  • Faulty oil temperature sensor
  • Chafed or damaged wiring
  • Intermittent module fault

Diagnostic steps

  1. Scan for intermittent codes
  2. Wiggle test wiring and connectors
  3. Monitor sensor data during driving
  4. Repair or replace faulty components
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